Monofunctional anionic initiators possessing amine functionalities are useful in preparing amino-terminated styrene-butadiene rubbers (SBR). See, for example, European Patent Application 593049A1 and U.S. Pat. No. 5,496,940 to Bridgestone Corporation. These elastomers have been shown to possess increased rebound, decreased rolling resistance, and lower heat build-up (reduced hysteresis). They are useful in forming improved, energy efficient tires, power belts, and mechanical goods.
Typically, the tertiary amino functionality is connected to the alkali metal via a connecting group. Exemplary tertiary amino initiators are illustrated, for example, in FIG. 1 below. Thus, the tertiary amine functionality of the resultant polymer is attached directly on the polymer backbone. ##STR1##
wherein:
M is an alkali metal, preferably lithium; PA1 R.sup.1 and R.sup.2 are alkyl, cycloalkyl or aralkyl having from 1 to 12 carbon atoms; PA1 R.sup.3 is a linear-, branched-, or cyclo-alkylene having from 2 to 20 carbon; and PA1 R.sup.4 is a divalent alkylene, oxy- or amino-alkylene, or substituted alkylene having 6 to 20 carbon atoms. See U.S. Pat. Nos. 5,332,810 and 5,496,940. PA1 Z is a halogen atom; PA1 R.sup.1 is selected from the group consisting of organic groups containing from 1 to about 12 carbon atoms and a bridging bond; PA1 each R.sup.2 is independently selected from the group consisting of hydrogen, organic groups containing from 1 to about 12 carbon atoms and a bridging bond; PA1 each R.sup.3 is independently selected from the group consisting of hydrogen, organic groups containing from 1 to about 12 carbon atoms; PA1 a is an integer from 4 to about 16; and PA1 b is an integer from 0 to about 12. These materials, however, were not very efficient electrophiles, as relatively low incorporation of tertiary amine functionality was obtained (11-73%). PA1 M is an alkali metal; PA1 R.sup.1 is chiral or achiral and is selected from the group consisting of saturated and unsaturated, linear and branched, optionally silyl-, amino-, or oxy-substituted, C3-C16 alkyl; and saturated and unsaturated, linear and branched, C3 -C16 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; PA1 R.sup.2 is chiral or achiral and is selected from the group consisting of saturated and unsaturated, linear and branched, optionally silyl-, amino-, or oxy-substituted, C1-C16 alkyl; saturated and unsaturated, optionally silyl-, amino-, or oxy-substituted, C3-C16 cycloalkyl; saturated and unsaturated, linear and branched, substituted C1-C16 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; and saturated and unsaturated substituted C3-C16 cycloalkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; PA1 R.sup.3 is a hydrocarbon connecting group or tether selected from the group consisting of saturated and unsaturated, linear and branched C1-C25 alkyl; saturated and unsaturated C3-C25 cycloalkyl; saturated and unsaturated substituted C1-C25 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; and saturated and unsaturated substituted C3-C25 cycloalkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl, with the proviso that the nitrogen atom and the alkali metal are separated by three or more carbon atoms; PA1 Q is a saturated or unsaturated hydrocarbyl group derived by incorporation of one or more conjugated diene hydrocarbons, one or more alkenylsubstituted aromatic compounds, or mixtures of one or more dienes with one or more alkenylsubstituted aromatic compounds into the M--R.sup.3 linkage; and PA1 n is an integer from 1 to 5. PA1 M is an alkali metal; PA1 R.sup.1 is chiral or achiral and is selected from the group consisting of saturated and unsaturated, linear and branched, optionally silyl-, amino-, or oxy-substituted, C3-C16 alkyl; and saturated and unsaturated, linear and branched, C3-C16 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; PA1 R.sup.2 is chiral or achiral and is selected from the group consisting of saturated and unsaturated, linear and branched, optionally silyl-, amino-, or oxy-substituted, C1-C16 alkyl; saturated and unsaturated, optionally silyl-, amino-, or oxy-substituted, C3-C16 cycloalkyl; saturated and unsaturated, linear and branched, substituted C1-C16 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; and saturated and unsaturated substituted C3-C16 cycloalkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; and PA1 R.sup.3 is a hydrocarbon connecting group or tether selected from the group consisting of saturated and unsaturated, linear and branched C1-C25 alkyl; saturated and unsaturated C3-C25 cycloalkyl; saturated and unsaturated substituted C1-C25 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; and saturated and unsaturated substituted C3-C25 cycloalkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl, with the proviso that the nitrogen atom and the alkali metal are separated by three or more carbon atoms. PA1 X is halogen selected from the group consisting of chlorine, bromine and iodine; and R.sup.1, R.sup.2, and R.sup.3 are as defined above. These halides are commercially available or can be prepared using techniques known in the art. PA1 M is an alkali metal; PA1 R.sup.1 is chiral or achiral and is selected from the group consisting of saturated and unsaturated, linear and branched, optionally silyl-, amino-, or oxy-substituted, C3-C16 alkyl; and saturated and unsaturated, linear and branched, C3-C16 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; PA1 R.sup.2 is chiral or achiral and is selected from the group consisting of saturated and unsaturated, linear and branched, optionally silyl-, amino-, or oxy-substituted, C1-C16 alkyl; saturated and unsaturated, optionally silyl-, amino-, or oxy-substituted, C3-C16 cycloalkyl; saturated and unsaturated, linear and branched, substituted C1-C16 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; and saturated and unsaturated substituted C3-C16 cycloalkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; PA1 R.sup.3 is a hydrocarbon connecting group or tether selected from the group consisting of saturated and unsaturated, linear and branched C1-C25 alkyl; saturated and unsaturated C3-C25 cycloalkyl; saturated and unsaturated substituted C1-C25 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; and saturated and unsaturated substituted C3-C25 cycloalkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl, with the proviso that the nitrogen atom and the alkali metal are separated by three or more carbon atoms; PA1 Q is a saturated or unsaturated hydrocarbyl group derived by incorporation of one or more conjugated diene hydrocarbons, one or more alkenylsubstituted aromatic compounds, or mixtures of one or more dienes with one or more alkenylsubstituted aromatic compounds into the M--R.sup.3 linkage; and PA1 n is an integer from 1 to 5. PA1 M is an alkali metal; PA1 R.sup.1 is chiral or achiral and is selected from the group consisting of saturated and unsaturated, linear and branched, optionally silyl-, amino-, or oxy-substituted, C3-C16 alkyl; and saturated and unsaturated, linear and branched, C3-C16 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; PA1 R.sup.2 is chiral or achiral and is selected from the group consisting of saturated and unsaturated, linear and branched, optionally silyl-, amino-, or oxy-substituted, C1-C16 alkyl; saturated and unsaturated, optionally silyl-, amino-, or oxy-substituted, C3-C16 cycloalkyl; saturated and unsaturated, linear and branched, substituted C1-C16 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; and saturated and unsaturated substituted C3-C16 cycloalkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; PA1 R.sup.3 is a hydrocarbon connecting group or tether selected from the group consisting of saturated and unsaturated, linear and branched C1-C25 alkyl; saturated and unsaturated C3-C25 cycloalkyl; saturated and unsaturated substituted C1-C25 alkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl; and saturated and unsaturated substituted C3-C25 cycloalkyl containing saturated or unsaturated lower alkyl, aryl, or substituted aryl, with the proviso that the nitrogen atom and the alkali metal are separated by three or more carbon atoms; PA1 Q is a saturated or unsaturated hydrocarbyl group derived by incorporation of one or more conjugated diene hydrocarbons, one or more alkenylsubstituted aromatic compounds, or mixtures of one or more dienes with one or more alkenylsubstituted aromatic compounds into the M--R.sup.3 linkage; and PA1 n is an integer from 1 to 5, PA1 R.sup.1, R.sup.2, R.sup.3, Q and n are as defined above; PA1 n is an integer from 0 to 5; PA1 P is a saturated or unsaturated hydrocarbyl group derived by incorporation of one or more compounds selected from the group consisting of conjugated dienes, alkenylsubstituted aromatic hydrocarbons and mixtures thereof; PA1 z is an integer from 2 to 10,000; and PA1 FG is hydrogen or a protected or unprotected functional group. PA1 FIG. 7 EQU X--Z--T--(A--R.sup.4 R.sup.5 R.sup.6).sub.m PA1 X is halogen selected from the group consisting of chloride, bromide and iodide; PA1 Z is a branched or straight chain hydrocarbon connecting group which contains 1-25 carbon atoms, optionally substituted with aryl or substituted aryl; PA1 T is selected from the group consisting of oxygen, sulfur, and nitrogen and mixtures thereof, PA1 A is an element selected from Group IVa of the Periodic Table of the Elements; PA1 R.sup.4, R.sup.5, and R.sup.6 are each independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, and substituted cycloalkyl, or R.sup.6 is optionally a --(CR.sup.7 R.sup.8).sub.1 -- group linking two A when m is 2, wherein R.sup.7 and R.sup.8 are each independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, and substituted cycloalkyl and 1 is an integer from 1 to 7; and PA1 m is 1 when T is oxygen or sulfur, and 2 when T is nitrogen. Thus the skilled artisan will appreciate that R.sup.6 as used herein includes the group ##STR9## PA1 R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, Q, Z, T, A, n and m have the meanings ascribed above (i.e., FG is --Z--T--(AR.sup.4 R.sup.5 R.sup.6).sub.m). PA1 R.sup.1, R.sup.2, R.sup.3, Q, P, Z, T, m, n and z have the meanings ascribed above. PA1 R.sup.1, R.sup.2, R.sup.3, Q, P, Z, T, n and z have the meanings ascribed above; and PA1 X is selected from the group consisting of polymer segments derived by incorporation of at least one comonomer reacted with T. PA1 R.sup.1, R.sup.2, R.sup.3, Q, P, n, and z have the meanings ascribed above; PA1 L is a residue of a multifunctional linking agent, such as divinylbenzene; and PA1 v is from 3 to 30. As the skilled artisan will appreciate, each R.sup.1, R.sup.2, R.sup.3, Q, P, n, and z can differ if different living polymers are prepared and coupled.
Recently, a method of incorporating tertiary amine functionality was described in U.S. Pat. No. 5,736,617, to Bridgestone Corporation. This patent is directed to use of an electrophile, described generically in FIG. 2, to quench a living polymer anion. ##STR2##
wherein: